Pakistani opposition leader Benazir Bhutto has been killed in a gun and bomb attack after a rally in the city of Rawalpindi, her party said.

"She has been martyred," party official Rehman Malik said.

Ms Bhutto, 54, died in hospital in Rawalpindi. Ary-One Television said she had been shot in the head.

Police said a suicide bomber fired shots at Ms Bhutto as she was leaving the rally venue in a park before blowing himself up.

"The man first fired at Bhutto's vehicle. She ducked and then he blew himself up," police officer Mohammad Shahid said.

Police said 16 people had been killed in the blast. Earlier, party officials said Ms Bhutto was safe.

A Reuters witness said he saw about eight bodies on a road.

An Interior Ministry spokesman said initial reports suggested it was a suicide bombing and more than 10 people had been killed.

A suicide bomber killed nearly 150 people in an attack on Ms Bhutto on October 18 as she paraded through the southern city of Karachi after returning home from eight years in self-imposed exile.

Earlier, gunmen opened fire on supporters of another former prime minister, Nawaz Sharif, from an office of the party that supports President Pervez Musharraf, killing four Sharif supporters, police said.

Mr Sharif was several kilometres away from the shooting and was on his way to Rawalpindi after attending a rally.

Mr Sharif, who was overthrown by Mr Musharraf in a 1999 coup and allowed back into the country just last month after seven years in exile, blamed supporters of the pro-Musharraf party for the violence.

But a spokesman for the party denied that its workers were involved.

The shooting occurred near an office of the pro-Musharraf Pakistan Muslim League (Q).

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